Chemical vapor deposition process

ABSTRACT

The present invention relates to chemical vapor deposition processes related to the manufacture of integrated circuit devices. In accordance with one embodiment of the present invention, a process for forming an electrical contact to a silicon substrate is provided wherein a semiconductor wafer is positioned in a reaction chamber wherein the semiconductor wafer includes an insulating layer disposed over a semiconductor substrate, and the insulating layer defines a contact opening therein. The contact opening defines insulating side wall regions therein. The insulating side walls extend from an upper surface region of the insulating layer to an exposed semiconductor region of the semiconductor substrate. A set of reactants are introduced into the reaction chamber, RF plasma is generated in the vicinity of the semiconductor wafer, and the temperature and pressure of the reaction chamber is regulated. The introduction of the reactants, the generation e RF plasma, and the regulation of the temperature and pressure is controlled so as to form a primary film over the upper surface region of the insulating layer over the insulating side wall regions, and over the exposed semiconductor region of the semiconductor substrate. A nitrogen-based gas is introduced into the reaction chamber and a nitridizing RF plasma is generated in the vicinity of the semiconductor wafer so as to nitridize the primary film formed over the upper surface region, the insulating side wall regions, and the exposed semiconductor region. An electrical contact is formed in the contact opening.

BACKGROUND AND SUMMARY OF THE INVENTION

The present invention relates to chemical vapor deposition processesrelated to the manufacture of integrated circuit devices. The presentinventors have recognized a need for an improved chemical vapordeposition process for use in integrated circuit manufacture and, moreparticularly, a need for an improved process for forming an electricalcontact to a semiconductor substrate.

In accordance with one embodiment of the present invention, a chemicalvapor deposition process is provided. A semiconductor wafer ispositioned in a reaction chamber. The semiconductor wafer includes aninsulating layer disposed over a silicon substrate. The insulating layerdefines a contact opening therein, the contact opening defininginsulating side wall regions therein, the insulating side wallsextending from an upper surface region of the insulating layer to anexposed silicon region of the silicon substrate. A set of reactants areintroduced into the reaction chamber. RF plasma is generated in thevicinity of the semiconductor wafer and the temperature and pressure ofthe reaction chamber are regulated.

The introduction of the reactants, the generation of the RF plasma, andthe regulation of the temperature and pressure are controlled so as toform a primary film over the upper surface region of the insulatinglayer, over the insulating side wall regions, and over the exposedsilicon region of the silicon substrate. The primary film is formed overthe upper surface region and the insulating side wall regions accordingto the following chemical reaction

TiCl₄+H₂→Ti+A

The primary film is formed over the exposed silicon region according tothe following chemical reaction

TiCl₄+H₂+Si→TiSi+A

Si represents silicon present in the silicon substrate and A representsa non-film forming component of the chemical reactions. The primary filmis characterized by a first thickness a over the upper surface regionand a second thickness b over the exposed silicon region. The firstthickness a is substantially less than the second thickness b.

The process may further comprise introducing a nitrogen-based gas intothe reaction chamber and generating a nitridizing RF plasma in thevicinity of the semiconductor wafer so as to nitridize the primary filmformed over the upper surface region, the insulating side wall regions,and the exposed silicon region. The nitridizing process causesconversion of the primary film formed over the upper surface region andthe insulating side wall regions to a TiN layer and formation of a TiNpassivation layer over the primary film formed over the exposed siliconregion.

The first thickness a may comprise titanium and may be about ½ themagnitude of the second thickness b. The second thickness b of theprimary film may comprise TiSi. The temperature of the reaction chambermay be regulated in the range of between about 500° C. and about 700° C.The pressure of the reaction chamber may be regulated in the range ofbetween about 500 Pa and about 700 Pa. The set of reactants may beintroduced into the reaction chamber with an inert gas, e.g., helium.The non-film forming component may include HCI, He, and combinationsthereof.

The process may further comprise introducing a nitrogen-based gas intothe reaction chamber and generating a nitridizing RF plasma in thevicinity of the semiconductor wafer so as to nitridize the primary filmformed over the upper surface region, the insulating side wall regions,and the exposed silicon region. The nitridizing process may cause theprimary film formed over the upper surface region and the insulatingside wall regions to be converted to TiN and may cause the primary filmformed over the exposed silicon region to be passivated with a layer ofTiN. Prior to introducing the nitrogen-based gas into the reactionchamber, the reaction chamber may be purged of TiCl₄.

The exposed silicon region of the silicon substrate typically comprisesan active area of a semiconductor device and may, for example, be adiffusion region, a source region of a transistor, a drain region of atransistor, and a collector region of a transistor.

In accordance with another embodiment of the present invention, achemical vapor deposition process is provided wherein a semiconductorwafer is positioned in a reaction chamber wherein the semiconductorwafer includes an insulating layer disposed over a semiconductorsubstrate, and the insulating layer defines a contact opening therein.The contact opening defines insulating side wall regions therein. Theinsulating side walls extend from an upper surface region of theinsulating layer to an exposed semiconductor region of the semiconductorsubstrate. A set of reactants are introduced into the reaction chamber,RF plasma is generated in the vicinity of the semiconductor wafer, andthe temperature and pressure of the reaction chamber is regulated.

The introduction of the reactants, the generation of the RF plasma, andthe regulation of the temperature and pressure is controlled so as toform a primary film over the upper surface region of the insulatinglayer, over the insulating side wall regions, and over the exposedsemiconductor region of the semiconductor substrate. A nitrogen-basedgas is introduced into the reaction chamber and a nitridizing RF plasmais generated in the vicinity of the semiconductor wafer so as tonitridize the primary film formed over the upper surface region, theinsulating side wall regions, and the exposed semiconductor region.

In accordance with yet another embodiment of the present invention, achemical vapor deposition process is provided wherein a semiconductorwafer is positioned in a reaction chamber. The semiconductor waferincludes an insulating layer disposed over a silicon substrate and theinsulating layer defines a contact opening therein. The contact openingdefines insulating side wall regions therein, the insulating side wallsextend from an upper surface region of the insulating layer to anexposed silicon region of the silicon substrate. A set of reactants areintroduced into the reaction chamber, RF plasma is generated in thevicinity of the semiconductor wafer, and the temperature and pressure ofthe reaction chamber are regulated. The RF plasma is generated at apower of about 1000 W and the temperature of the reaction chamber isregulated in the range of between about 500° C. and about 700° C.

The introduction of the reactants, the generation of the RF plasma, andthe regulation of the temperature and pressure is controlled so as toform a primary film over the upper surface region of the insulatinglayer, over the insulating side wall regions, and over the exposedsilicon region of the silicon substrate. The primary film is formed overthe upper surface region and the insulating side wall regions accordingto the following chemical reaction

TiCl₄+H₂→Ti+A

The primary film is formed over the exposed silicon region according tothe following chemical reaction

TiCl₄+H₂+Si→TiSi+A

Si represents silicon present in the silicon substrate and A representsa non-film forming component of the chemical reactions, wherein theprimary film is characterized by a first thickness a over the uppersurface region and a second thickness b over the exposed silicon region,and wherein the first thickness a is substantially less than the secondthickness b.

In accordance with yet another embodiment of the present invention, achemical vapor deposition process is provided wherein a semiconductorwafer is positioned in a reaction chamber. The semiconductor waferincludes an insulating layer disposed over a silicon substrate and theinsulating layer defines a contact opening therein. The contact openingdefines insulating side wall regions therein, the insulating side wallsextend from an upper surface region of the insulating layer to anexposed silicon region of the silicon substrate. A set of reactants areintroduced into the reaction chamber, RF plasma is generated in thevicinity of the semiconductor wafer, and the temperature and pressure ofthe reaction chamber is regulated. The RF plasma is generated at a powerof about 1000 W and the temperature of the reaction chamber is regulatedin the range of between about 500° C. and about 700° C. The introductionof the reactants, the generation of the RF plasma, and the regulation ofthe temperature and pressure is controlled so as to form a Ti film overthe upper surface region of the insulating layer and over the insulatingside wall regions and so as to form a TiSi film over the exposed siliconregion of the silicon substrate. The primary film is characterized by afirst thickness a over the upper surface region and a second thickness bover the exposed silicon region. The first thickness a is substantiallyless than the second thickness b.

In accordance with yet another embodiment of the present invention, aprocess for forming an electrical contact to a silicon substrate isprovided wherein a semiconductor wafer is positioned in a reactionchamber. The semiconductor wafer includes an insulating layer disposedover a silicon substrate. The insulating layer defines a contact openingtherein, the contact opening defining insulating side wall regionstherein, the insulating side walls extending from an upper surfaceregion of the insulating layer to an exposed silicon region of thesilicon substrate. A set of reactants are introduced into the reactionchamber. RF plasma is generated in the vicinity of the semiconductorwafer and the temperature and pressure of the reaction chamber areregulated.

The introduction of the reactants, the generation of the RF plasma, andthe regulation of the temperature and pressure are controlled so as toform a primary film over the upper surface region of the insulatinglayer, over the insulating side wall regions, and over the exposedsilicon region of the silicon substrate. The primary film is formed overthe upper surface region and the insulating side wall regions accordingto the following chemical reaction

TiCl₄+H₂→Ti+A

The primary film is formed over the exposed silicon region according tothe following chemical reaction

TiCl₄+H₂+Si→TiSi+A

Si represents silicon present in the silicon substrate and A representsa non-film forming component of the chemical reactions. The primary filmis characterized by a first thickness a over the upper surface regionand a second thickness b over the exposed silicon region. The firstthickness a is substantially less than the second thickness b. Anelectrical contact is formed in the contact opening.

A nitrogen-based gas may be introduced into the reaction chamber and anitridizing RF plasma may be generated in the vicinity of thesemiconductor wafer so as to nitridize the primary film formed over theupper surface region, the insulating side wall regions, and the exposedsilicon region. The nitridizing process may cause conversion of theprimary film formed over the upper surface region and the insulatingside wall regions to a TiN layer, and formation of a TiN passivationlayer over the primary film formed over the exposed silicon region.

The electrical contact may be formed by depositing a layer of conductivematerial over the primary film formed over the upper surface region andin the contact opening over the primary film and removing the portion ofthe layer of conductive material overlying the portion of the primaryfilm overlying the upper surface region. The removal of the portion ofthe layer of conductive material is characterized by a process that issubstantially less effective in removing the primary film. The portionof the primary film is removed following removal of the conductivematerial.

The electrical contact may be formed by depositing a layer of conductivematerial over the portion of the primary film overlying the uppersurface region and in the contact opening over the primary film. Theelectrical contact may further be formed by removing the portion of thelayer of conductive material overlying the portion of the primary filmoverlying the upper surface region. The removal of the portion of thelayer of conductive material is characterized by a process that issubstantially less effective in removing the primary film. The portionof the primary film overlying the upper surface region may be removedfollowing removal of the conductive material.

In accordance with yet another embodiment of the present invention, aprocess for forming an electrical contact to a silicon substrate isprovided wherein a semiconductor wafer is positioned in a reactionchamber wherein the semiconductor wafer includes an insulating layerdisposed over a semiconductor substrate, and the insulating layerdefines a contact opening therein. The contact opening definesinsulating side wall regions therein. The insulating side walls extendfrom an upper surface region of the insulating layer to an exposedsemiconductor region of the semiconductor substrate. A set of reactantsare introduced into the reaction chamber, RF plasma is generated in thevicinity of the semiconductor wafer, and the temperature and pressure ofthe reaction chamber is regulated.

The introduction of the reactants, the generation of the RF plasma, andthe regulation of the temperature and pressure is controlled so as toform a primary film over the upper surface region of the insulatinglayer, over the insulating side wall regions, and over the exposedsemiconductor region of the semiconductor substrate. A nitrogen-basedgas is introduced into the reaction chamber and a nitridizing RF plasmais generated in the vicinity of the semiconductor wafer so as tonitridize the primary film formed over the upper surface region, theinsulating side wall regions, and the exposed semiconductor region. Anelectrical contact is formed in the contact opening.

The electrical contact may be formed by depositing a layer of conductivematerial over the portion of the primary film overlying the uppersurface region and in the contact opening over the primary film. Theportion of the layer of conductive material overlying the portion of theprimary film overlying the upper surface region may be removed. Theremoval of the portion of the layer of conductive material may becharacterized by a process that is substantially less effective inremoving the primary film. The portion of the primary film is removedfollowing removal of the conductive material.

In accordance with yet another embodiment of the present invention, aprocess for forming an electrical contact to a silicon substrate isprovided wherein a semiconductor wafer is positioned in a reactionchamber. The semiconductor wafer includes an insulating layer disposedover a silicon substrate and the insulating layer defines a contactopening therein. The contact opening defines insulating side wallregions therein, the insulating side walls extend from an upper surfaceregion of the insulating layer to an exposed silicon region of thesilicon substrate. A set of reactants are introduced into the reactionchamber, RF plasma is generated in the vicinity of the semiconductorwafer, and the temperature and pressure of the reaction chamber areregulated. The RF plasma is generated at a power of about 1000 W and thetemperature of the reaction chamber is regulated in the range of betweenabout 500° C. and about 700° C.

The introduction of the reactants, the generation of the RF plasma, andthe regulation of the temperature and pressure is controlled so as toform a primary film over the upper surface region of the insulatinglayer, over the insulating side wall regions, and over the exposedsilicon region of the silicon substrate. The primary film is formed overthe upper surface region and the insulating side wall regions accordingto the following chemical reaction

TiCl₄+H₂→Ti+A

The primary film is formed over the exposed silicon region according tothe following chemical reaction

TiCl₄+H₂+Si→TiSi+A

Si represents silicon present in the silicon substrate and A representsa non-film forming component of the chemical reactions, wherein theprimary film is characterized by a first thickness a over the uppersurface region and a second thickness b over the exposed silicon region,and wherein the first thickness a is substantially less than the secondthickness b.

In accordance with yet another embodiment of the present invention, aprocess for forming an electrical contact to a silicon substrate isprovided wherein a semiconductor wafer is positioned in a reactionchamber. The semiconductor wafer includes an insulating layer disposedover a silicon substrate and the insulating layer defines a contactopening therein. The contact opening defines insulating side wallregions therein, the insulating side walls extend from an upper surfaceregion of the insulating layer to an exposed silicon region of thesilicon substrate. A set of reactants are introduced into the reactionchamber, RF plasma is generated in the vicinity of the semiconductorwafer, and the temperature and pressure of the reaction chamber isregulated. The RF plasma is generated at a power of about 1000 W and thetemperature of the reaction chamber is regulated in the range of betweenabout 500° C. and about 700° C. The introduction of the reactants, thegeneration of the RF plasma, and the regulation of the temperature andpressure is controlled so as to form a Ti film over the upper surfaceregion of the insulating layer and over the insulating side wall regionsand so as to form a TiSi film over the exposed silicon region of thesilicon substrate. The primary film is characterized by a firstthickness a over the upper surface region and a second thickness b overthe exposed silicon region. The first thickness a is substantially lessthan the second thickness b.

Accordingly, it is an object of the present invention to provide animproved chemical vapor deposition process and, more particularly, animproved process for forming an electrical contact to a semiconductorsubstrate. Other objects of the present invention will be apparent inlight of the description of the invention embodied herein.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The following detailed description of the preferred embodiments of thepresent invention can be best understood when read in conjunction withthe following drawings, where like structure is indicated with likereference numerals and in which: FIGS. 1-6 illustrate a chemical vapordeposition and electrical connection formation process according to thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An improved chemical vapor deposition process and, more particularly, animproved process for forming an electrical contact to a semiconductorsubstrate are illustrated in FIGS. 1-6. In order to provide a clearillustration of the invention, the dimensions of the various materiallayers illustrated in FIGS. 1-6 are not presented to scale. Similarly,the profiles and surface topography of the various material layersillustrated in FIGS. 1-6 have been made artificially uniform to preserveclarity of illustration.

Referring initially to FIG. 1, a semiconductor wafer 10 including aninsulating layer 12 disposed over a silicon substrate 14 is positionedin a reaction chamber 20. The silicon substrate 14 includes an activearea 16 formed therein. The active area 16 may, for example, comprise adiffusion region, a source, drain, or collector region of a transistor.

The insulating layer 12 defines a contact opening 18 therein. Thecontact opening 18 defines insulating side walls 19 extending from anupper surface region 13 of the insulating layer 12 to an exposed siliconregion 15 of the silicon substrate 14. The dimensions of the contacthole 18 illustrated in the figures of the present application are notpresented to scale. Typically, the contact hole 18 would have a greaterdepth and smaller width than that illustrated.

A set of reactants and an inert gas are introduced into the reactionchamber 20 and an RF plasma is generated in the vicinity of thesemiconductor wafer 10. The particular arrangement of the reactionchamber and the RF source are beyond the scope of the present inventionand may be gleaned from conventional RF plasma enhanced chemical vapordeposition arrangements, such as those described in U.S. Pat. Nos.5,665,640 and 5,173,327, the disclosures of which are incorporatedherein by reference.

In one embodiment of the present invention, the temperature of thereaction chamber is regulated in the range of between about 500° C. andabout 700° C. The pressure of the reaction chamber is regulated in therange of between about 500 Pa and about 700 Pa. The set of reactants areintroduced into the reaction chamber with an inert gas, such as helium.

Although the present invention is illustrated herein with specificreference to a silicon semiconductor substrate 14 and a titanium-basedprimary film 22, it is contemplated by the present invention that othersemiconductor and film materials may be utilized according to thepresent invention.

For the purposes of describing and defining the present invention,formation of a material, layer, or film “on” a substrate or layer refersto formation in contact with a surface of the substrate or layer.Formation “over” a substrate or layer refers to formation above asurface of the substrate or layer, in contact with a surface of thesubstrate or layer, partially above and partially within the interior ofthe substrate or layer, or within the substrate at the surface of thesubstrate or layer.

Referring now to FIG. 2, the introduction of the reactants, thegeneration of the RF plasma, and the regulation of the temperature andpressure are controlled so as to form a primary film 22 over (i) theupper surface region 13 of the insulating layer 12, (ii) the insulatingside wall regions 19, and (iii) the exposed silicon region 15 of thesilicon substrate 14. The primary film 22 is formed over the uppersurface region 13 and the insulating side wall regions 19 according tothe following chemical reaction

TiCl₄+H₂→Ti+A

In contrast, the primary film 22 is formed over the exposed siliconregion 15 according to the following chemical reaction

TiCl₄+H₂+Si→TiSi+A

Si represents silicon present in the silicon substrate and A representsa non-film forming component of the chemical reactions (e.g., HCl).Non-film forming components include HCl and He.

The two different portions of the primary film 22 are illustrated inFIGS. 2-6 as 22A and 22B. This selective deposition process leads toformation of a primary film 22 characterized by a first thickness a overthe upper surface region 13 and a second thickness b over the exposedsilicon region. Because the reaction is selective, the first thickness ais substantially less than the second thickness b. Typically, the firstthickness a is about ½the magnitude of the second thickness b.

As is clearly illustrated in FIGS. 2-6, the two different portions 22Aand 22B of the primary film 22 define collectively a non-uniformthickness.

After formation of the primary film 22, the reaction chamber 20 ispurged of TiCl₄ and the primary film 22 is nitridized by introducing anitrogen-based gas into the reaction chamber 20 and generating anitridizing RF plasma in the vicinity of the semiconductor wafer 10. Asis illustrated in FIG. 3, where the primary film 22 comprises Ti andTiSi, this nitridizing process causes conversion of the primary film 22formed over the upper surface region 13 and the insulating side wallregions 19 to a TiN layer 22C and formation of a TiN passivation layer22D over the primary film 22 formed over the exposed silicon region 15.

Referring now to FIGS. 4-6 a manner of forming an electrical contact 40in the contact opening 18 is illustrated. According to one embodiment ofthe present invention, the electrical contact is formed by initiallydepositing a layer of conductive material 30 over theconverted/passivated primary film 22 and in the contact opening 18. Inone embodiment of the present invention, the conductive material 30comprises WSi_(x). The Si content of the WSi_(x) may be enhanced tominimize any reactions with the TiSi or the TiN. Other suitableconductive materials include, and are not limited to, othertungsten-based materials, including pure tungsten.

Next, the portion of the layer of conductive material 30 overlying theconverted primary film 22 over the upper surface region 13 is removed,typically through an etching process (see FIG. 5). The removal of theportion of the layer of conductive material 30 overlying the convertedprimary film 22 over the upper surface region 13 is characterized by aprocess that is substantially less effective in removing the convertedprimary film 22. In this manner, the converted primary film 22 protectsthe insulating layer during removal of the conductive material 30. Thepreferred process for removal is specific to the material used for theconductive material 30 and the converted primary film 22 over the uppersurface region 13. For the purposes of describing and defining thepresent invention, a process that is “substantially” less effective inremoving the converted primary film 22 than in removing the conductivefilm is a process that leaves enough of the converted primary film 22 toprotect the insulating layer during removal of the conductive material30. The converted primary film 22 over the upper surface region 13 isremoved following removal of the portion of the layer of conductivematerial 30 (see FIG. 6).

Having described the invention in detail and by reference to preferredembodiments thereof, it will be apparent that modifications andvariations are possible without departing from the scope of theinvention defined in the appended claims.

What is claimed is:
 1. A chemical vapor deposition process, wherein asemiconductor wafer is positioned in a reaction chamber, saidsemiconductor wafer including an insulating layer disposed over asilicon substrate and said insulating layer defining a contact openingtherein, said contact opening defining insulating side wall regionstherein, said insulating side walls extending from an upper surfaceregion of said insulating layer to an exposed silicon region of saidsilicon substrate, said process comprising: introducing a set ofreactants into said reaction chamber; generating a RF plasma in thevicinity of said semiconductor wafer and regulating temperature andpressure of said reaction chamber; and controlling said introduction ofsaid reactants, said generation of said RF plasma, and said regulationof said temperature and pressure so as to form a primary film over saidupper surface region of said insulating layer, over said insulating sidewall regions, and over said exposed silicon region of said siliconsubstrate, wherein said primary film is formed over said upper surfaceregion and said insulating side wall regions according to the followingchemical reaction TiCl₄+H₂→Ti+A  wherein said primary film is formedover said exposed silicon region according to the following chemicalreaction TiCl₄+H₂+Si→TiSi+A where Si represents silicon present in saidsilicon substrate and A represents a non-film forming component of saidchemical reactions, wherein said primary film is characterized by afirst thickness a over said upper surface region and a second thicknessb over said exposed silicon region, and wherein said first thickness ais less than said second thickness b.
 2. A chemical vapor depositionprocess as claimed in claim 1 wherein said process further comprises:introducing a nitrogen-based gas into said reaction chamber; andgenerating a nitridizing RF plasma in the vicinity of said semiconductorwafer so as to nitridize said primary film formed over said uppersurface regional, said insulating side wall regions, and said exposedsilicon region, wherein said nitridizing process causes conversion ofsaid primary film formed over said upper surface region and saidinsulating side wall regions to a TiN layer, and said nitridizingprocess causes formation of a TiN passivation layer over said primaryfilm formed over said exposed silicon region.
 3. A chemical vapordeposition process as claimed in claim 1 wherein said first thickness ais about ½ the magnitude of said second thickness b.
 4. A chemical vapordeposition process as claimed in claim 1 wherein said first thickness aof said primary film comprises titanium.
 5. A chemical vapor depositionprocess as claimed in claim 1 wherein said second thickness b of saidprimary film comprises TiSi.
 6. A chemical vapor deposition process asclaimed in claim 1 wherein said temperature of said reaction chamber isregulated in the range of between about 500° C. and about 700° C. andwherein said pressure of said reaction chamber is regulated in the rangeof between about 500 Pa and about 700 Pa.
 7. A chemical vapor depositionprocess as claimed in claim 1 wherein said temperature of said reactionchamber is regulated in the range of between about 500° C. and about700° C.
 8. A chemical vapor deposition process as claimed in claim 1wherein said pressure of said reaction chamber is regulated in the rangeof between about 500 Pa and about 700 Pa.
 9. A chemical vapor depositionprocess as claimed in claim 1 wherein said set of reactants areintroduced into said reaction chamber with an inert gas.
 10. A chemicalvapor deposition process as claimed in claim 9 wherein said inert gascomprises helium.
 11. A chemical vapor deposition process as claimed inclaim 1 wherein said non-film forming component is selected from HCl,He, and combinations thereof.
 12. A chemical vapor deposition process asclaimed in claim 1 wherein said process further comprises: introducing anitrogen-based gas into said reaction chamber; and generating anitridizing RF plasma in the vicinity of said semiconductor wafer so asto nitridize said primary film formed over said upper surface region,said insulating side wall regions, and said exposed silicon region. 13.A chemical vapor deposition process as claimed in claim 12 wherein saidnitridizing process causes said primary film formed over said uppersurface region and said insulating side wall regions to be converted toTiN.
 14. A chemical vapor deposition process as claimed in claim 12wherein said nitridizing process causes said primary film formed oversaid exposed silicon region to be passivated with a layer of TiN.
 15. Achemical vapor deposition process as claimed in claim 12 furthercomprising the step of purging said reaction chamber of TiCi₄ prior tointroducing said nitrogen-based gas into said reaction chamber.
 16. Achemical vapor deposition process as claimed in claim 1 furthercomprising the step of providing said exposed silicon region of saidsilicon substrate as an active area of a semiconductor device.
 17. Achemical vapor deposition process as claimed in claim 16 wherein saidactive area comprises an active area selected from a group including adiffusion region, a source region of a transistor, a drain region of atransistor, and a collector region of a transistor.
 18. A chemical vapordeposition process, wherein a semiconductor wafer is positioned in areaction chamber, said semiconductor wafer including an insulating layerdisposed over a semiconductor substrate and said insulating layerdefining a contact opening therein, said contact opening defininginsulating side wall regions therein, said insulating side wallsextending from an upper surface region of said insulating layer to anexposed semiconductor region of said semiconductor substrate, saidprocess comprising: introducing a set of reactants into said reactionchamber; generating a RF plasma in the vicinity of said semiconductorwafer and regulating temperature and pressure of said reaction chamber;controlling said introduction of said reactants, said generation of saidRF plasma, and said regulation of said temperature and pressure so as toform a primary film over said upper surface region of said insulatinglayer, over said insulating side wall regions, and over said exposedsemiconductor region of said semiconductor substrate; introducing anitrogen-based gas into said reaction chamber; and generating anitridizing RF plasma in the vicinity of said semiconductor wafer so asto nitridize said primary film formed over said upper surface region,said insulating side wall regions, and said exposed semiconductorregion.
 19. A chemical vapor deposition process, wherein a semiconductorwafer is positioned in a reaction chamber, said semiconductor waferincluding an insulating layer disposed over a silicon substrate and saidinsulating layer defining a contact opening therein, said contactopening defining insulating side wall regions therein, said insulatingside walls extending from an upper surface region of said insulatinglayer to an exposed silicon region of said silicon substrate, saidprocess comprising: introducing a set of reactants into said reactionchamber; generating a RF plasma in the vicinity of said semiconductorwafer and regulating temperature and pressure of said reaction chamber,wherein said RF plasma is generated at power of about 1000 W and saidtemperature of said reaction chamber is regulated in the range ofbetween about 500° C. and about 700° C.; and controlling saidintroduction of said reactants, said generation of said RF plasma, andsaid regulation of said temperature and pressure so as to form a primaryfilm over said upper surface region of said insulating layer, over saidinsulating side wall regions,and over said exposed silicon region ofsaid silicon substrate, wherein said primary film is formed over saidupper surface region and said insulating side wall regions according tothe following chemical reaction TiCl₄+H₂→Ti+A  wherein said primary filmis formed over said exposed silicon region according to the followingchemical reaction TiCl₄+H₂+Si→TiSi+A where Si represents silicon presentin said silicon substrate and A represents a non-film forming componentof said chemical reactions, wherein said primary film is characterizedby a first thickness a over said upper surface region and a secondthickness b over said exposed silicon region, and wherein said firstthickness a is less than said second thickness b.
 20. A chemical vapordeposition process as claimed in claim 19 wherein said process furthercomprises: introducing a nitrogen-based gas into said reaction chamber;and generating a nitridizing RF plasma in the vicinity of saidsemiconductor wafer so as to nitridize said primary film formed oversaid upper surface region, said insulating side wall regions, and saidexposed silicon region, wherein said nitridizing process causesconversion of said primary film formed over said upper surface regionand said insulating side wall regions to a TiN layer, and saidnitridizing process causes formation of a TiN passivation layer oversaid primary film formed over said exposed silicon region.
 21. Achemical vapor deposition process, wherein a semiconductor wafer ispositioned in a reaction chamber, said semiconductor wafer including aninsulating layer disposed over a silicon substrate and said insulatinglayer defining a contact opening therein, said contact opening defininginsulating side wall regions therein, said insulating side wallsextending from an upper surface region of said insulating layer to andexposed silicon region of said silicon substrate, said processcomprising: introducing a set of reactants into said reaction chamber;generating a RF plasma in the vicinity of said semiconductor wafer andregulating temperature and pressure of said reaction chamber, whereinsaid RF plasma is generated at a power of about 1000 W and saidtemperature of said reaction chamber is regulated in the range ofbetween 500° C. and about 700° C.; and controlling said introduction ofsaid reactants, said generation of said RF plasma, and said regulationof said temperature and pressure so as to form a Ti film over said uppersurface region of said insulating layer and over said insulating sidewall regions and so as to form a TiSi film over said exposed siliconregion of said silicon substrate, wherein said primary film ischaracterized by a first thickness a over said upper surface region anda second thickness b over said exposed silicon region, and wherein saidfirst thickness a is less than said second thickness b.
 22. A chemicalvapor deposition process as claimed in claim 21 wherein said processfurther comprises: introducing a nitrogen-based gas into said reactionchamber; and generating a nitridizing RF plasma in the vicinity of saidsemiconductor wafer so as to nitridize said primary film formed oversaid upper surface region, said insulating side wall regions, and saidexposed silicon region, wherein said nitridizing process causesconversion of said primary film formed over said upper surface regionand said insulating side wall regions to a TiN layer, and saidnitridizing process causes formation of a TiN passivation layer oversaid primary film formed over said exposed silicon region.
 23. Achemical vapor deposition process, wherein a semiconductor wafer ispositioned in a reaction chamber, said semiconductor wafer including aninsulating layer disposed over a silicon substrate and said insulatinglayer defining a contact opening therein, said contact opening defininginsulating side wall regions therein, said insulating side wallsextending from an upper surface region of said insulating to an exposedsilicon region of said silicon substrate, said process comprising:introducing a set of reactants and an inert gas into said reactionchamber; generating a RF plasma in the vicinity of said semiconductorwafer and regulating temperature and pressure of said reaction chamber,wherein said RF plasma is generated at a power of about 1000 W and saidtemperature of said reaction chamber is regulated in the range ofbetween about 500° C. and about 700° C.; controlling said introductionof said reactants, said generation of said RF plasma, and saidregulation of said temperature and pressure so as to form a primary filmover said upper surface region of said insulating layer, over saidinsulating side wall regions, and over said exposed silicon region ofsaid silicon substrate, wherein said primary film is formed over saidupper surface region and said insulating side wall regions according tothe following chemical reaction TiCl₄+H₂→Ti+A  wherein said primary filmis formed over said exposed silicon region according to the followingchemical reaction TiCl₄+H₂+Si→TiSi+A where Si represents silicon presentin said silicon substrate and A represents a non-film forming componentof said chemical reactions, wherein said primary film is characterizedby a fist thickness a over said upper surface region and a secondthickness b over said exposed silicon region, and wherein said firstthickness a is less than said second thickness b; purging said reactionchamber of TiCl₄; introducing a nitrogen-based gas into said reactionchamber; and generating a nitridizing RF plasma in the vicinity of saidsemiconductor wafer so as to nitridize said primary film formed oversaid upper surface region, said insulating side wall regions, and saidexposed silicon region, wherein said nitridizing process causesconversion of said primary film formed over said upper surface regionand said insulating side wall regions to a TiN layer, and saidnitridizing process causes formation of a TiN passivation layer oversaid primary film formed over said exposed silicon region.
 24. A processfor forming an electrical contact to a silicon substrate, wherein asemiconductor wafer is positioned in a reaction chamber, saidsemiconductor wafer including an insulating layer disposed over asilicon substrate and said insulating layer defining a contact openingtherein, said contact opening defining insulating side wall regionstherein, said insulating side walls extending from an upper surfaceregion of said insulating layer to an exposed silicon region of saidsilicon substrate, said process comprising: introducing a set ofreactants into said reaction chamber; generating a RF plasma in thevicinity of said semiconductor wafer and regulating temperature andpressure of said reaction chamber; controlling said introduction of saidreactants, said generation of said RF plasma, and said regulation ofsaid temperature and pressure so as to form a primary film over saidupper surface region of said insulating layer, over said insulating sidewall regions, and over said exposed silicon region of said siliconsubstrate, wherein said primary film is formed over said upper surfaceregion and said insulating side wall regions according to the followingchemical reaction TiCl₄+H₂→Ti+A  wherein said primary film is formedover said exposed silicon region according to the following chemicalreaction TiCl₄+H₂+Si→TiSi+A where Si represents silicon present in saidsilicon substrate and A represents a non-film forming component of saidchemical reactions, wherein said primary film is characterized by afirst thickness a over said upper surface region and a second thicknessb over said exposed silicon region, and wherein said first thickness ais less than said second thickness b; and forming an electrical contactin said contact opening.
 25. A process for forming an electrical contactto a silicon substrate as claimed in claim 24 wherein said processfurther comprises: introducing a nitrogen-based gas into said reactionchamber; and generating a nitridizing RF plasma in the vicinity of saidsemiconductor wafer so as to nitridize said primary film formed oversaid upper surface region, said insulating side wall regions, and saidexposed silicon region, wherein said nitridizing process causesconversion of said primary film formed over said upper surface regionand said insulating side wall regions to a TiN layer, and saidnitridizing process causes formation of a TiN passivation layer oversaid primary film formed over said exposed silicon region.
 26. A processfor forming an electrical contact to a silicon substrate as claimed inclaim 24 wherein said electrical contact is formed by: depositing alayer of conductive material over said primary film formed over saidupper surface region and in said contact opening over said primary film;removing the portion of said layer of conductive material overlying saidportion of said primary film overlying said upper surface region,wherein said removal of said portion of said layer of conductivematerial is characterized by a process that is substantially lesseffective in removing said primary film; and removing said portion ofsaid primary film following removal of said conductive material.
 27. Aprocess for forming an electrical contact to a silicon substrate asclaimed in claim 24 wherein said electrical contact is formed bydepositing a layer of conductive material over said portion of saidprimary film overlying said upper surface region and in said contactopening over said primary film.
 28. A process for forming an electricalcontact to a silicon substrate as claimed in claim 27 wherein saidelectrical contact is further formed by removing the portion of saidlayer of conductive material overlying said portion of said primary filmoverlying said upper surface region.
 29. A process for forming anelectrical contact to a silicon substrate as claimed in claim 28 whereinsaid removal of said portion of said layer of conductive material ischaracterized by a process that is substantially less effective inremoving said primary film.
 30. A process for forming an electricalcontact to a silicon substrate as claimed in claim 28 wherein saidportion of said primary film overlying said upper surface region isremoved following removal of said conductive material.
 31. A process forforming an electrical contact to a silicon substrate as claimed in claim24 further comprising the step of providing said exposed silicon regionof said silicon substrate as an active area of a semiconductor device.32. A process for forming an electrical contact to a silicon substrateas claimed in claim 31 further comprising the step of providing saidactive area as an active area selected from a group including adiffusion region, a source region of a transistor, a drain region of atransistor, and a collector region of a transistor.
 33. A process forforming an electrical contact to a semiconductor substrate, wherein asemiconductor wafer is positioned in a reaction chamber, saidsemiconductor wafer including an insulating layer disposed over asemiconductor substrate and said insulating layer defining a contactopening therein, said contact opening defining insulating side wallregions therein, said insulating side walls extending from an uppersurface region of said insulating layer to an exposed semiconductorregion of said semiconductor substrate, said process comprising:introducing a set of reactants into said reaction chamber; generating aRF plasma in the vicinity of said semiconductor wafer and regulatingtemperature and pressure of said reaction chamber; controlling saidintroduction of said reactants, said generation of said RF plasma, andsaid regulation of said temperature and pressure so as to form a primaryfilm over said upper surface region of said insulating layer, over saidinsulating side wall regions, and over said exposed semiconductor regionof said semiconductor substrate; introducing a nitrogen-based gas intosaid reaction chamber; generating a nitridizing RF plasma in thevicinity of said semiconductor wafer so as to nitridize said primaryfilm formed over said upper surface region, said insulating side wallregions, and said exposed semiconductor region; and forming anelectrical contact in said contact opening.
 34. A process for forming anelectrical contact to a silicon substrate as claimed in claim 33 whereinsaid electrical contact is formed by: depositing a layer of conductivematerial over said portion of said primary film overlying said uppersurface region and in said contact opening over said primary film;removing the portion of said layer of conductive material overlying saidportion of said primary film overlying said upper surface region,wherein said removal of said portion of said layer of conductivematerial is characterized by a process that is substantially lesseffective in removing said primary film; and removing said portion ofsaid primary film following removal of said conductive material.
 35. Aprocess for forming an electrical contact to a silicon substrate,wherein a semiconductor wafer is positioned in a reaction chamber, saidsemiconductor wafer including an insulating layer disposed over asilicon substrate and said insulating layer defining a contact openingtherein, said contact opening defining insulating side wall regionstherein, said insulating side walls extending from an upper surfaceregion of said insulating layer to an exposed silicon region of saidsilicon substrate, said process comprising: introducing a set ofreactants into said reaction chamber; generating a RF plasma in thevicinity of said semiconductor wafer and regulating temperature andpressure of said reaction chamber, wherein said RF plasma is generatedat a power of about 1000 W and said temperature of said reaction chamberis regulated in the range of between about 500° C. and about 700° C.;controlling said introduction of said reactants, said generation of saidRF plasma, and said regulation of said temperature and pressure so as toform a primary film over said upper surface region of said insulatinglayer, over said insulating side wall regions, and over said exposedsilicon region of said silicon substrate, wherein said primary film isformed over said upper surface region and said insulating side wallregions according to the following chemical reaction TiCl₄+H₂→Ti+A wherein said primary film is formed over said exposed silicon regionaccording to the following chemical reaction TiCl₄+H₂+Si→TiSi+A where Sirepresents silicon present in said silicon substrate and A represents anon-film forming component of said chemical reactions, wherein saidprimary film is characterized by a first thickness a over said uppersurface region and a second thickness b over said exposed siliconregion, and wherein said first thickness a is less than said secondthickness b; and forming an electrical contact in said contact opening.36. A process for forming an electrical contact to a silicon substrateas claimed in claim 35 wherein said process further comprises:introducing a nitrogen-based gas into said reaction chamber; andgenerating a nitridizing RF plasma in the vicinity of said semiconductorwafer so as to nitridize said primary film formed over said uppersurface region, said insulating side wall regions, and said exposedsilicon region, wherein said nitridizing process causes conversion ofsaid primary film formed over said upper surface region and saidinsulating side wall regions to a TiN layer, and said nitridizingprocess causes formation of a TiN passivation layer over said primaryfilm formed over said exposed silicon region.
 37. A process for formingan electrical contact to a silicon substrate as claimed in claim 35wherein said electrical contact is formed by: depositing a layer ofconductive material over said portion of said primary film overlyingsaid upper surface region and in said contact opening over said primaryfilm; removing the portion of said layer of conductive materialoverlying said portion of said primary film overlying said upper surfaceregion, wherein said removal of said portion of said layer of conductivematerial is characterized by a process that is substantially lesseffective in removing said primary film; and removing said portion ofsaid primary film following removal of said conductive material.
 38. Aprocess for forming an electrical contact to a silicon substrate,wherein a semiconductor wafer is positioned in a reaction chamber, saidsemiconductor wafer including an insulating layer disposed over asilicon substrate and said insulating layer defining a contact openingtherein, said contact opening defining insulating side wall regionstherein, said insulating side walls extending from an upper surfaceregion of said insulating layer to an exposed silicon region of saidsilicon substrate, said process comprising: introducing a set ofreactants into said reaction chamber; generating a RF plasma in thevicinity of said semiconductor wafer and regulating temperature andpressure of said reaction chamber, wherein said RF plasma is generatedat a power of about 1000 W and said temperature of said reaction chamberis regulated in the range of between about 500° C. and about 700° C.;controlling said introduction of said reactants, said generation of saidRF plasma, and said regulation of said temperature and pressure so as toform a Ti film over said upper surface region of said insulating layerand over said insulating side wall regions and go as to form a TiSi filmover said exposed silicon region of said silicon substrate, wherein saidprimary film is characterized by a first thickness a over said uppersurface region and a second thickness b over said exposed siliconregion, and wherein said first thickness a is less than said secondthickness b; and forming an electrical contact in said contact opening.39. A process for forming an electrical contact to a silicon substrateas claimed in claim 38 wherein said process further comprises:introducing a nitrogen-based gas into said reaction chamber; andgenerating a nitridizing RF plasma in the vicinity of said semiconductorwafer so as to nitridize said primary film formed over said uppersurface region, said insulating side wall regions, and said exposedsilicon region, wherein said nitridizing process causes conversion ofsaid primary film formed over said upper surface region and saidinsulating side wall regions to a TiN layer, and said nitridizingprocess causes formation of a TiN passivation layer over said primaryfilm formed over said exposed silicon region.
 40. A process for formingan electrical contact to a silicon substrate as claimed in claim 38wherein said electrical contact is formed by: depositing a layer ofconductive material over said portion of said primary film overlyingsaid upper surface region and in said contact opening over said primaryfilm; removing the portion of said layer of conductive materialoverlying said portion of said primary film overlying said upper surfaceregion, wherein said removal of said portion of said layer of conductivematerial is characterized by a process that is substantially lesseffective in removing said primary film; and removing said portion ofsaid primary film following removal of said conductive material.
 41. Aprocess for forming an electrical contact to a silicon substrate,wherein a semiconductor wafer is positioned in a reaction chamber, saidsemiconductor wafer including an insulating layer disposed over asilicon substrate and said insulating layer defining a contact openingtherein, said contact opening defining insulating side wall regionstherein, said insulating side walls extending from an upper surfaceregion of said insulating layer to an exposed silicon region of saidsilicon substrate, said process comprising: introducing a set ofreactants and an inert gas into said reaction chamber; generating a RFplasma in the vicinity of said semiconductor wafer and regulatingtemperature and pressure of said reaction chamber, wherein said RFplasma is generated at a power of about 1000 W and said temperature ofsaid reaction chamber is regulated in the range of between about 500° C.and about 700° C.; controlling said introduction of said reactants, saidgeneration of said RF plasma, and said regulation of said temperatureand pressure so as to form a primary film over said upper surface regionof said insulating layer, over said insulating side wall regions, andover said exposed silicon region of said silicon substrate, wherein saidprimary film is formed over said upper surface region and saidinsulating side wall regions according to the following chemicalreaction TiCl₄+H₂→Ti+A  wherein said primary film is formed over saidexposed silicon region according to the following chemical reaction TiCl₄+H₂+Si→TiSi+A where Si represents silicon present in said siliconsubstrate and A represents a non-film forming component of said chemicalreactions, wherein said primary film is characterized by a firstthickness a over said upper surface region and a second thickness b oversaid exposed silicon region, and wherein said first thickness a is lessthan said second thickness b; purging said reaction chamber of TiCl₄;introducing a nitrogen-based gas into said reaction chamber; generatinga nitridizing RF plasma in the vicinity of said semiconductor wafer soas to nitridize said primary film formed over said upper surface region,said insulating side wall regions, and said exposed silicon region,wherein said nitridizing process causes conversion of said primary filmformed over said upper surface region and said insulating side wallregions to a TiN layer, and said nitridizing process causes formation ofa TiN passivation layer over said primary film formed over said exposedsilicon region; and forming an electrical contact in said contactopening.
 42. A process for forming an electrical contact to a siliconsubstrate as claimed in claim 41 wherein said electrical contact isformed by: depositing a layer of conductive material over said portionof said primary film overlying said upper surface region and in saidcontact opening over said primary film; removing the portion of saidlayer of conductive material overlying said portion of said primary filmoverlying said upper surface region, wherein said removal of saidportion of said layer of conductive material is characterized by aprocess that is substantially less effective in removing said primaryfilm; and removing said portion of said primary film following removalof said conductive material.